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Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 September 1999 - 31 October 2000, Philip W. Sadler, Robert E. Harris, John E. Olney, Robert J. Latour Dec 2000

Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 September 1999 - 31 October 2000, Philip W. Sadler, Robert E. Harris, John E. Olney, Robert J. Latour

Reports

To document continued compliance with Federal law, the Anadromous Fishes Program of the Virginia Institute of Marine Science (VIMS) has monitored the size and age composition, sex ratio and maturity schedules of the spawning striped bass stock in the Rappahannock River since December 1981 utilizing commercial pound nets and, since 1991, variable-mesh experimental gill nets. Spawning stock assessment was expanded to include the James River in 1994 utilizing 11 commercial fyke nets and variable-mesh experimental gill nets. The use of fyke nets was discontinued after 1997. In conjunction with the monitoring studies, tagging programs have been conducted in the James …


Temperature Effects On Export Production In The Open Ocean, Ea Laws, Pg Falkowki, Walker O. Smith Jr., H Ducklow, Jj Mccarthy Dec 2000

Temperature Effects On Export Production In The Open Ocean, Ea Laws, Pg Falkowki, Walker O. Smith Jr., H Ducklow, Jj Mccarthy

VIMS Articles

A pelagic food web model was formulated with the goal of developing a quantitative understanding of the relationship between total production, export production, and environmental variables in marine ecosystems. The model assumes that primary production is partitioned through both large and small phytoplankton and that the food web adjusts to changes in the rate of allochthonous nutrient inputs in a way that maximizes stability, i.e., the ability of the system to return to steady state following a perturbation. The results of the modeling exercise indicate that ef ratios, defined as new production/total production = export production/total production, are relatively insensitive …


Seasonal Variations Of Size-Fractionated Phytoplankton Along The Salinity Gradient In The York River Estuary, Virginia (Usa), Y Sin, Rl Wetzel, I. C. Anderson Oct 2000

Seasonal Variations Of Size-Fractionated Phytoplankton Along The Salinity Gradient In The York River Estuary, Virginia (Usa), Y Sin, Rl Wetzel, I. C. Anderson

VIMS Articles

The dynamics of phytoplankton size structure were investigated in the freshwater, transitional and estuarine zones of the York River over an annual cycle. The contribution of large cells (microplankton, >20 mu m) to total concentrations of chlorophyll a increased downstream during winter, whereas that of small cells (nanoplankton, 3-20 mu m; picoplankton,m) increased downstream during summer. In the freshwater region, the contribution of micro phytoplankton to total concentrations of chlorophyll a was significant during warm seasons (spring and summer) but not during colder seasons (winter), whereas the contribution of small-sized cells (especially picoplankton) increased during cold seasons. Temperature, light and …


Changes In Bacterioplankton Metabolic Capabilities Along A Salinity Gradient In The York River Estuary, Virginia, Usa, G. E. Schultz, H. W. Ducklow Sep 2000

Changes In Bacterioplankton Metabolic Capabilities Along A Salinity Gradient In The York River Estuary, Virginia, Usa, G. E. Schultz, H. W. Ducklow

VIMS Articles

Changes in metabolic capabilities of bacterial communities along the estuarine salinity gradient may affect the extent of organic matter processing and bacterial growth and accumulation during transit through the system; As part of a larger study of estuarine microbial processes, we attempted to quantify differences in bacterial community structure using Biolog plates. Biolog GN plates (Biolog, Inc., Hayward, CA, USA) were used to determine differences in bacterioplankton community metabolic potential. Biolog GN microplates are 96-well microtiter plates in which each well contains an individual carbon source as well the redox dye tetrazolium violet. As bacteria grow and oxidize each substrate, …


Evaluating The Recruitment Of American Eel, Anguilla Rostrata, To The Potomac - Spring 2000 : March 2000 - June 2000, Patrick J. Geer, Julie A. Weeder, Steven Hammond, Rudolph Lukacovic Sep 2000

Evaluating The Recruitment Of American Eel, Anguilla Rostrata, To The Potomac - Spring 2000 : March 2000 - June 2000, Patrick J. Geer, Julie A. Weeder, Steven Hammond, Rudolph Lukacovic

Reports

Measures of juvenile recruitment success have long been recognized as a valuable fisheries management tool. In the Chesapeake Bay, these measures have provided reliable indicators for future year class strength for blue crabs (Lipcius and van Engel, 1990), striped bass (Goodyear, 1985), and several other recreationally important fishes (Geer and Austin, 1999).

The American eel, Anguilla rostrata, is a valuable commercial species along the entire Atlantic coast from New Brunswick to Florida. Landings along the U.S. Atlantic coast have varied from 290 MT in 1962 to a high of 1600 MT in 1975 (NMFS, 1999). In recent years there seems …


Environmental Survey Of Potential Sand Resource Sites, Offshore Delaware And Maryland : Final Report, Virginia Institute Of Marine Science Aug 2000

Environmental Survey Of Potential Sand Resource Sites, Offshore Delaware And Maryland : Final Report, Virginia Institute Of Marine Science

Reports

  • Technical summary / Carl H. Hobbs
  • Non-technical summary / Carl H. Hobbs
  • Part. 1. Benthic mapping and resource evaluation of potential sand mining areas, offshore Mayland and Delaware, 1998-1999 / G.R. Cutter and R.J. Diaz
  • Part. 2. Transitory species (vertebrate nekton) / John A. Musick
  • Part. 3. Literature survey of reproductive finfish and ichthyoplankton present in proposed sand mining locations within the Middle Atlantic Bight / John Olney, Donna Marie Bilkovic
  • Part. 4. Potential modifications to waves due to dredging and other oceanographic considerations / Jerome P.-Y. Maa, Sung C. Kim
  • Part. 5. Maryland-Delaware shoreline : long-term trends and short-term …


Monitoring Relative Abundance Of American Shad In Virginia's Rivers Annual Report 1999, John E. Olney Sr., John M. Hoenig Jul 2000

Monitoring Relative Abundance Of American Shad In Virginia's Rivers Annual Report 1999, John E. Olney Sr., John M. Hoenig

Reports

A moratorium on the taking of American shad (Alosa sapidissima) in the Chesapeake Bay and its tributaries was established by the Virginia Marine Resources Commission (VMRC) beginning 1 January 1994. The prohibition applied to both recreational and commercial fishers. The moratorium was imposed at a time when commercial catch rates of American shad in Virginia's rivers were experiencing declines. Data from the commercial fishery were the best available for assessing the status of individual stocks. Catch-per-unit-effort (CPUE) data were compiled from logbooks that recorded landings by commercial fishermen using staked gill nets at various locations throughout the middle reaches of …


Local Demographics Of The Polychaete Chaetopterus Pergamentaceus Within The Lower Chesapeake Bay And Relationships To Environmental Gradients, Ml Thompson, Linda C. Schaffner Jul 2000

Local Demographics Of The Polychaete Chaetopterus Pergamentaceus Within The Lower Chesapeake Bay And Relationships To Environmental Gradients, Ml Thompson, Linda C. Schaffner

VIMS Articles

Chaetopterus pergamentaceus is an abundant and functionally important species within the soft sediment, subtidal benthic community of lower Chesapeake Bay. The present study elucidates spatial relationships in density, individual ash-free dry weight, total station ash-free dry weight and growth rates for juveniles and adults from 2 yrs of sampling (1994, 1995) at 12 stations in the lower Chesapeake Bay. A strong inverse relationship (r(2) = 0.69) was observed between growth rates and total density for juveniles when data from a low(1994) and high(1995) recruitment year were considered. Common parameters among stations characterized by high density/low growth were: (1) depth (maximum …


Bacterial Consumption Of Doc During Transport Through A Temperate Estuary, Pa Raymond, Je Bauer Jul 2000

Bacterial Consumption Of Doc During Transport Through A Temperate Estuary, Pa Raymond, Je Bauer

VIMS Articles

Bacterial utilization of natural levels of dissolved organic carbon (DOC) was measured in the York River estuary, a sub-estuary of the Chesapeake Bay. This study was undertaken in order to elucidate spatial and temporal changes in bacterial carbon utilization and to evaluate its importance as a pathway for organic matter transformation in estuaries. Multiple pools of DOC were defined based on decomposition kinetics. The first pool (G(1)) made up a mean of 2.8% of total DOC and had turnover times of less than or equal to 5 d. The second pool (G(2)) comprised an average of 4.9% of total DOC …


The Crest, Summer 2000, Virginia Institute Of Marine Science Jul 2000

The Crest, Summer 2000, Virginia Institute Of Marine Science

Reports

Table of Contents:

  • VIMS Scientists Successfully Spawn Cobia
  • NMFS Faculty Position Established at VIMS
  • Scientists Discover New Species of Perkinsus
  • Researchers Discover New Pollutants Infiltrating Virginia Rivers
  • Sea Scallop Research Resumed in June
  • MARSH Project Will Help Save Tidal Wetlands
  • Virginia's Changing Coastal Community - Indicators of Change
  • New Pound-Net Design Spares Young Fish
  • VIMS Scientist Studies Oysters in India
  • American Shad Focus of Unique Study
  • From the Coleman Bridge to Menai Bridge:
  • VIMS Professor Leads Field-Course in Wales
  • New Experimental Design Course for Teachers
  • Students Teaching Students
  • Horseshoe Crab Research is Timely
  • Award Winning Bridge Website Receives Renewed Funding …


Restoration Of Submerged Aquatic Vegetation (Sav) In The Tidal Freshwater James River: Year 2, Ken Moore, Kevin Segerblom, Betty Neikirk, James Fishman Jul 2000

Restoration Of Submerged Aquatic Vegetation (Sav) In The Tidal Freshwater James River: Year 2, Ken Moore, Kevin Segerblom, Betty Neikirk, James Fishman

Reports

No abstract provided.


Zoosporulation Of A New Perkinsus Species Isolated From The Gills Of The Softshell Clam Mya Arenaria, Sm Mclaughlin, Bd Tall, A Shaheen, Ee Elsayed, M Faisal Jun 2000

Zoosporulation Of A New Perkinsus Species Isolated From The Gills Of The Softshell Clam Mya Arenaria, Sm Mclaughlin, Bd Tall, A Shaheen, Ee Elsayed, M Faisal

VIMS Articles

A gill-associated Perkinsus sp. isolated from the softshell clam (Myo arenaria) is described as a new species, P. chesapeaki sp. nov. Examination of the parasite in seawater cultures revealed life cycle stages and zoosporulation processes similar to those described for other species of the genus Perkinsus. Prezoosporangia developed thickened cell walls upon contraction of the cytoplasm and development of a distinctive clear area between the cell wall and the protoplast. Successive bipartition of the protoplast led to the formation of hundred's of zoospores within mature sporangia. Zoospores were released into seawater through one or more discharge tubes, Ultrastructural studies revealed …


Restoration Of Submerged Aquatic Vegetation (Sav) In The Tidal Freshwater James River: 1999 Pilot Study, Ken Moore, R J. Orth, James Fishman Jun 2000

Restoration Of Submerged Aquatic Vegetation (Sav) In The Tidal Freshwater James River: 1999 Pilot Study, Ken Moore, R J. Orth, James Fishman

Reports

No abstract provided.


Basinsim 1.0 A Windows-Based Watershed Modeling Package, Ting Dai, Richard L. Wetzel, Tyler R.L. Christensen, E. Amy Lewis May 2000

Basinsim 1.0 A Windows-Based Watershed Modeling Package, Ting Dai, Richard L. Wetzel, Tyler R.L. Christensen, E. Amy Lewis

Reports

BasinSim 1.0 for Windows is the product of a NOAA Coastal Zone Management grant (through the Virginia Coastal Resources Management Program) awarded to Drs. Ting Dai, R. L. Wetzel, I. C. Anderson, and L. W. Haas at the Virginia Institute of Marine Science, College of William and Mary in 1998. Additional support has been provided for the development and testing of this package and production of this user’s guide by grants from Virginia’s Chesapeake Bay Local Assistance Department (CBLAD). BasinSim 1.0 is a desktop simulation system that predicts sediment and nutrient loads for small to mid-sized watersheds. The simulation system …


Piankatank River Shoreline Situation Report, Marcia Berman, Harry Berquist, Tamia Rudnicky, Julie Glover Apr 2000

Piankatank River Shoreline Situation Report, Marcia Berman, Harry Berquist, Tamia Rudnicky, Julie Glover

Reports

This shoreline inventory has been developed as a tool for assessing conditions along the tidal shoreline of the river, and tributaries in the Piankatank River Watershed. Recent conditions are reported for three zones within the immediate riparian river area: riparian land use, bank and buffers, and the shoreline. A series of maps and tabular data are published to illustrate and quantify results of an extensive survey in the watershed. This survey extends from the mouth of the Dragon Run to the mouth of the Piankatank River, at the confluence with the Chesapeake Bay. Coverage extends slightly south and east, including …


A Comparative Field Study Of Crassostrea Ariakensis And Crassostrea Virginica In Relation To Salinity In Virginia, Gustavo W. Calvo, Mark Luckenbach, Standish K. Allen Jr., Eugene M. Burreson Mar 2000

A Comparative Field Study Of Crassostrea Ariakensis And Crassostrea Virginica In Relation To Salinity In Virginia, Gustavo W. Calvo, Mark Luckenbach, Standish K. Allen Jr., Eugene M. Burreson

Reports

In accordance with the Rational Plan for Testing Application of Non-Native Oyster Species (VIMS 1996) we conducted a field experiment to examine survival, growth and disease susceptibility of Crassostrea ariakensis (=rivularis) in relation to salinity in Virginia. The performance of triploid C. ariakensis in comparison with that of diploid C. virginica, (n = 250, age = 2 years, mean shell height = 60- 64 mm) was evaluated at replicate sites within low, medium, and high salinity regimes (respectively, < 15‰, 15-25‰, > 25‰) in Chesapeake Bay and the Atlantic Coast. During the course of this study, from June 1998 to September 1999, there was …


Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Mj Church, Da Hutchins, Hw Ducklow Feb 2000

Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Mj Church, Da Hutchins, Hw Ducklow

VIMS Articles

The importance of resource limitation in controlling bacterial growth in the high-nutrient, low-chlorophyll (HNLC) region of the Southern Ocean was experimentally determined during February and March 1998. Organic- and inorganic-nutrient enrichment experiments were performed between 42 degrees S and 55 degrees S along 141 degrees E. Bacterial abundance, mean cell volume, and [H-3]thymidine and [H-3]leucine incorporation were measured during 4- to 5-day incubations. Bacterial biomass, production, and rates of growth all responded to organic enrichments in three of the four experiments. These results indicate that bacterial growth was constrained primarily by the availability of dissolved organic matter. Bacterial growth in …


Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 September 1998 - 31 October 1999, Philip Sadler, Robert E. Harris, Jason Romine, John E. Olney Sr. Jan 2000

Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 September 1998 - 31 October 1999, Philip Sadler, Robert E. Harris, Jason Romine, John E. Olney Sr.

Reports

No abstract provided.


Monitoring Relative Abundance Of American Shad In Virginia's Rivers Annual Report 1998, John E. Olney, John Hoenig Jan 2000

Monitoring Relative Abundance Of American Shad In Virginia's Rivers Annual Report 1998, John E. Olney, John Hoenig

Reports

A moratorium on the taking of American shad in the Chesapeake Bay and its tributaries was established by the Virginia Marine Resources Commission (VMRC) beginning 1 January 1994. The prohibition applied to both recreational and commercial fishers. The moratorium was imposed at a time when commercial catch rates of American shad in Virginia's rivers were experiencing declines. Data from the commercial fishery were the best available for assessing the status of individual stocks. Catch-per-unit-effort (CPUE) data were compiled from logbooks that recorded landings by commercial fishermen using staked gill nets at various locations throughout the middle reaches of the three …


Osmotic Tolerance And Volume Regulation In In Vitro Cultures Of The Oyster Pathogen Perkinsus Marinus, Cl O'Farrell, Jf La Peyre, Kt Paynter, Em Burreson Jan 2000

Osmotic Tolerance And Volume Regulation In In Vitro Cultures Of The Oyster Pathogen Perkinsus Marinus, Cl O'Farrell, Jf La Peyre, Kt Paynter, Em Burreson

VIMS Articles

Growth rate. cell size, osmotic tolerance, and volume regulation were examined in cells of Perkinsus marinus cultured in media of osmolalities ranging from 168 to 737 mOsm (6.5-27.0 ppt). Cells cultured at the low osmolalities of 168 and 256 mOsm (6.5 and 9.7 ppt) began log phase growth 4 days postsubculture, whereas cells cultured at the higher osmolalities 341, 433, and 737 mOsm (12.7. 16.0, and 27.0 ppt) began log phase growth 2 days postsubculture. During log phase growth, cells from the higher osmolalities 341, 433, and 737 mOsm had shorter doubling times than cells from the lower osmolalities 168 …


1999 Annual Awards, Virginia Institute Of Marine Science Jan 2000

1999 Annual Awards, Virginia Institute Of Marine Science

Miscellaneous

The Annual Awards ceremony is an occasion in which new employees and volunteers are introduced, employee service is recognized and student and faculty awards are presented.


Into The 21st Century ... Marine Science For Virginia, The Nation And The World, Virginia Institute Of Marine Science Jan 2000

Into The 21st Century ... Marine Science For Virginia, The Nation And The World, Virginia Institute Of Marine Science

Miscellaneous

Informational brochure on the Institute research and programs.


Ruth Dixon Turner 1914-2000 - In Memoriam, R Mann Jan 2000

Ruth Dixon Turner 1914-2000 - In Memoriam, R Mann

VIMS Articles

No abstract provided.


Strategies For Assessing The Implications Of Malformed Frogs For Environmental Health, Jg Burkhart, Robert C. Hale Jan 2000

Strategies For Assessing The Implications Of Malformed Frogs For Environmental Health, Jg Burkhart, Robert C. Hale

VIMS Articles

The recent increase in the incidence of deformities among natural frog populations has raised concern about the state of the environment and the possible impact of unidentified causative agents on the health of wildlife and human populations. An open workshop on Strategies for Assessing the Implications of Malformed Frogs for Environmental Health was convened on 4-5 December 1997 at the National Institute of Environmental Health Sciences in Research Triangle Park, North Carolina. The purpose of the workshop was to share information among a multidisciplinary group with scientific interest and responsibility for human and environmental health at the federal and state …


Oyster Reef Restoration: Convergence Of Harvest And Conservation Strategies, Dl Breitburg, Ld Coen, Mark Luckenbach, Roger L. Mann, M Posey, J. A. Wesson Jan 2000

Oyster Reef Restoration: Convergence Of Harvest And Conservation Strategies, Dl Breitburg, Ld Coen, Mark Luckenbach, Roger L. Mann, M Posey, J. A. Wesson

VIMS Articles

Oyster reef restoration, protection, and construction are important to meeting harvest, water quality, and fish habitat goals. However, the strategies needed to achieve harvest and conservation goals have often been considered to be at odds. We argue that these goals are. in fact, compatible and that the same strategies will promote a sustainable harvest of the resource, increased filtration of estuarine waters, and increased provision of structured habitat for finfish, crabs, and other organisms that utilize oyster reefs or receive benefit indirectly from them. Creation or designations of unharvested sites (refuge sites) are key components of these strategies. Unharvested reefs …


Mortality And Hematology Of Blue Crabs, Callinectes Sapidus, Experimentally Infected With The Parasitic Dinoflagellate Hematodinium Perezi, Jeffrey D. Shields, Christopher M. Squyars Jan 2000

Mortality And Hematology Of Blue Crabs, Callinectes Sapidus, Experimentally Infected With The Parasitic Dinoflagellate Hematodinium Perezi, Jeffrey D. Shields, Christopher M. Squyars

VIMS Articles

On the eastern seaboard of the United States, populations of the blue crab, Callinectes sapidus, experi-ence recurring outbreaks of a parasitic dinoflagellate, Hematodinium perezi. Epizootics fulminate in summer and autumn causing mortalities in high-salinity embayments and estuaries. In laboratory studies, we experimentally investigated host mortality due to the disease, assessed differential hemato-logical changes in infected crabs, and examined proliferation of the parasite.


Organic Matter Composition Of Sediments And The History Of Eutrophication And Anoxia In The Mesohaline Chesapeake Bay, Andrew R. Zimmerman Jan 2000

Organic Matter Composition Of Sediments And The History Of Eutrophication And Anoxia In The Mesohaline Chesapeake Bay, Andrew R. Zimmerman

Dissertations, Theses, and Masters Projects

To evaluate the effects of anthropogenic alteration of the Chesapeake Bay (CB) watershed since European settlement, the historical progression of eutrophication and anoxia in the mesohaline region of CB was reconstructed. Lipid biomarker and carbon and nitrogen stable isotopic and elemental composition of CB surficial sediments were examined seasonally in order to identify the present sources of organic matter to CB sediments and the processes controlling their distribution. Temporal variability in surficial sediment composition could be linked to seasonal changes in phytoplankton community composition and biomass while spatial variation was dominated by the delivery of alloclithonous versus autochthonous sources of …


Restoring The Oyster Reef Communities In The Chesapeake Bay: A Commentary, Roger L. Mann Jan 2000

Restoring The Oyster Reef Communities In The Chesapeake Bay: A Commentary, Roger L. Mann

VIMS Articles

Restoration of the oyster Crassostrea virginica resource to the Chesapeake Bay is a widely supported goal. This manuscript explores the questions of why, how, and in what time frame this should be attempted. Restoration goals based simply on support of a commercial fishery fail to address the role of the oyster as a cornerstone species within the Chesapeake Bay and should only be considered in the context of a long-term sustainable fishery exploitation. The argument is proffered that a restored resource sustaining a fishery at the historical harvest level is unrealistic, because: (1) harvest probably exceeded biological production for much …


Estimates Of Naked Goby (Gobiosoma Bosc), Striped Blenny (Chasmodes Bosquianus) And Eastern Oyster (Crassostrea Virginica) Larval Production Around A Restored Chesapeake Bay Oyster Reef, Jm Harding, Roger L. Mann Jan 2000

Estimates Of Naked Goby (Gobiosoma Bosc), Striped Blenny (Chasmodes Bosquianus) And Eastern Oyster (Crassostrea Virginica) Larval Production Around A Restored Chesapeake Bay Oyster Reef, Jm Harding, Roger L. Mann

VIMS Articles

Naked gobies (Gobiosoma bose) and striped blennies (Chasmodes bosquianus) rely on oyster reefs for nesting sites, feeding grounds, and refugia from predation by upper level piscivores. Seasonal densities of Eastern oysters (Crassostrea virginica), naked gobies, and striped blennies on Palace Bar Reef, Piankatank River, Virginia were quantified and used to develop species-specific larval production estimates. Densities of oyster adults, juveniles, and articulated shell valves (the result of recent mortality) did not significantly change from November 1995 to November 1996. Naked goby and striped blenny densities varied with substrate type and season; peak fish densities for both species were observed in …


Demonstration Of The Onshore Transport Of Larval Invertebrates By The Shoreward Movement Of An Upwelling Front, Al Shanks, J Largier, L Brink, J Brubaker, R Hooff Jan 2000

Demonstration Of The Onshore Transport Of Larval Invertebrates By The Shoreward Movement Of An Upwelling Front, Al Shanks, J Largier, L Brink, J Brubaker, R Hooff

VIMS Articles

Upwelling winds off North Carolina set up upwelling fronts. As the wind forcing relaxed following such a coastal upwelling event, we observed the upwelling front move onshore. The low-density surface water moved shoreward over the upwelled water, forming a convergence zone at the-front. This shoreward-moving front concentrated and transported larvae. Larval sergestid shrimp, spionid polychaete larvae, and the veligers of Odostomia sp. and Bittium sp, were concentrated on the seaward side of the moving convergence. Blue crab megalopae were concentrated at the surface immediately seaward of the front. These data demonstrate that a relaxing upwelling front can transport high concentrations …